Rules of conduct are designed to keep everybody safe, allow both sides to verify what they are looking at accurately, and prevent international incident. Little doubt that the Chinese are concerned about Hainan proxyimity, and posed a very real and blatant safety violation by rolling around the P-8....wouldn't surprise me to see F-22s scrambled to run intercepts on the bad guy. Maybe even follow them around a while???
That's beside the point. The real issue is surveillance and reconnaissance. It's unbalancing and strongly favors the stronger side.
Even when both side is equal, perfect information provides opportunity to attack when there is momentary weakness, while when both sides are opaque, then you cannot make that assumption.
With unequal power, this is acerbated, since weaker side is always weak, and perfect information invites knockout punch, while the weaker side cannot do the same. If both side are opaque, at least knockout punch cannot be achieved so easily.
Again, do you really want anyone to poke around your nuke assets? If all you are interested is in limited war, then you should avoid doing that because that will provoke the other side to use the nukes before they lose them. If you know that and insist on doing so, then they must suspect you are planning a total war.
Do this to the Russians, I think they will shoot you down. Chinese, at least, are courteous enough to give you a warning, as rude as it is.
I seriously don't think top people in Washington who is well versed in MAD issues will knowingly provoke China. Whoever authorized this overstepped his/her authority as this has ramification way above his/her pay grade.
If I remember correctly, the EP3 incident was partially caused by one such screw-up. There was a treaty with Russia reducing the surveillance intensity, so instead of just stopping flights, the area commander redirected those flights to China. China interpreted this, in conjunction with international situation (beginning of Bush Jr administration and neocons) as the are being targeted. Hence the increasingly aggressive response. And this was before China moved the SSBN to Hainan.
If you only worry about flight safety, you are missing the forest for the tree.
Edit:
By the way, Peter Lee at China Matters Blog implies this is a deliberate provocation by one faction of US Navy...